Getting an Aten Serial to USB adapter working on 10.9+
NOTE: ATEN have now written a driver for Yosemite that works! Not sure about the driver for Mavericks. Just download it here. Just install it, reboot and away you go.
I'm using an ATEN UC232A adapter. I got this from here. I've adapted it slightly for 10.9 (Mavericks).
1. Plug in your adapter and run "System Information" application and click on the USB devices, looking for "USB-Serial Conroller". When you click on it you'll get something like:
USB-Serial Controller D: Product ID: 0x2008 Vendor ID: 0x0557 (ATEN International Co. Ltd.) Version: 3.00 Speed: Up to 12 Mb/sec Manufacturer: Prolific Technology Inc. Location ID: 0x14100000 / 8 Current Available (mA): 500 Current Required (mA): 100
The Producut ID and Vendor ID numbers are important. You can use the "Calculator" app, to convert them to base 10: 0x2008=8200 and 0x0557=1367.
2. Download and install the drivers from the Prolific website here.
NOTE: The Aten UC232A and the Prolific PL2303 are basically the same device and the Prolific drivers are maintained!
3. After your reboot, edit /System/Library/Extensions/ProlificUsbSerial.kext/Contents/Info.plist
sudo vim /System/Library/Extensions/ProlificUsbSerial.kext/Contents/Info.plist
Find the idProduct and idVendor fields and change them to the values we calculated earlier:
<key>idProduct</key> <integer>8200</integer> <key>idVendor</key> <integer>1367</integer>
They both appear in two different places, so change both.
4. Unplug the adapter and restart the kernel extension (or just reboot):
sudo kextload /System/Library/Extensions/ProlificUsbSerial.kext
5. It should now be working.
You can now use it using your favourite terminal emulator or the screen command:
screen /dev/tty.usbserial 9600
Ctrl a \ to exit!